大采长综放工作面单位时间内瓦斯涌出量增大,经常造成工作面回风隅角和回风巷瓦斯质量浓度超限.通过分析综放工作面瓦斯涌出源,可以了解其瓦斯涌出特征.对阳泉三矿大采长K8206综放工作面初采期和回采期的瓦斯涌出规律的分析可知,初采期瓦斯涌出量具有大幅度波动性,其原因主要为采空区瓦斯不断地、周期性地涌入.正常回采期,只要高抽巷的抽放负压足够大,邻近层瓦斯涌入工作面的问题就能解决;而大采长综放工作面本煤层瓦斯涌出量增大,则需要增加通风量或者采用新的通风方式.
Methane emission rate per unit time is high in the big mining-length and fully mechanized topcoal caving face where the raised mechanization is used, and the concentration of methane exceeding limit in return airflow corner and return airflow roadway usually takes place. The feature of methane emission can be found by analysing methane headstream. The methane emission laws of the K8206 top'coal caving face are investigated during the initial mining stage and normal mining stage. The reason of large fluctuating is that methane swarms constantly and periodically from the goaf, and the abrupt roof caving and crannies occurring will also arose the unexpected methane effusing from the adjacent stratum. The problem of methane effusing from the adjacent stratum during normal mining stage could be resolved only by the suction pressure of the high-position alley. At the same time, methane effusing from the coal seam being worked increases, and the emphases of methane control could be put on the methane effusing from coal seam being worked.